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How Heat Sinks Work

Introduction to How Heat Sinks Work
Heat sinks are designed to prevent today's high-tech computers from over heating. See more computer hardware pictures.

Though the term heat sink probably isn't one most people think of when they hear the word computer, it should be. Without heat sinks, modern computers couldn't run at the speeds they do. Just as you cool down with a cold bottle of Gatorade after a high impact workout, heat sinks cool down your computer's processor after it runs multiple programs at once. And without a quality heat sink, your computer processor is at risk of overheating, which could destroy your entire system, costing you hundreds, even thousands of dollars.

But what exactly is a heat sink and how does it work? Simply put, a heat sink is an object that disperses heat from another object. They're most commonly used in computers, but are also found in cell phones, DVD players and even refrigerators. In computers, a heat sink is an attachment for a chip that prevents the chip from overheating and, in modern computers, it's as important as any other component.

If you aren't very tech-savvy, think of the heat sink like a car radiator. The same way a radiator draws heat away from your car's engine, a heat sink draws heat away from your computer's central processing unit (CPU). The heat sink has a thermal conductor that carries heat away from the CPU into fins that provide a large surface area for the heat to dissipate throughout the rest of the computer, thus cooling both the heat sink and processor. Both a heat sink and a radiator require airflow and, therefore, both have fans built in.

Before the 1990s, heat sinks were usually only necessary in large computers where the heat from the processor was a problem. But with the introduction of faster processors, heat sinks became essential in almost every computer because they tended to overheat without the aid of a cooling mechanism.

On the next page we'll take a look at some different types of heat sinks, as well as the scientific principles that explain how they work.